Radio access point testing apparatus and method of testing radio access point

ABSTRACT

A reception sensitivity is measured at a high precision. An access terminal function portion includes the transmitter part and receiver part of a communication terminal in a radio communication system. A path switch part effects switching to connect the input ends of receivers to antennas or to terminate them. The path switch part switches the paths of a signal from a transmitter and signals toward the receivers. An access point controller adjusts a packet error rate into a predetermined range, and obtains the reception sensitivity based on the transmission power of the access terminal function portion after the adjustment.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is a continuation application of applicationSer. No. 11/349,150, filed Feb. 8, 2006, now U.S. Pat. No. 7,353,020;which is a continuation-in-part of application Ser. No. 10/910,583,filed Aug. 4, 2004, now U.S. Pat. No. 7,366,508 which claims priority ofJapanese Application No. 2005-139727, filed May 12, 2005 and JapaneseApplication No. 2003-386193, filed Nov. 17, 2003, all of the disclosureof which are hereby incorporated by reference into this application.

BACKGROUND OF THE INVENTION

The present invention relates to a radio access point testing apparatusand a method of testing a radio access point, and more particularly to aradio access point testing apparatus and a method of testing a radioaccess point in a mobile communication system.

In operating the mobile communication system, the stability of thesystem is one of important factors. For the stable operation of thesystem, it is required to prevent the occurrence of any failure leadingto a system operation stop, and also to promptly detect the failure andresume the system operation in case of the occurrence of the failure.Accordingly, the failure detection circuit of the radio access point anda diagnostic method therefor are very important.

A transmitter and a receiver are mounted in the radio access point. Thefailure detection of the transmitter of them can be incarnatedcomparatively easily in such a way that part of a transmission mainsignal generated by the transmitter is branched and then monitored. Incontrast, the failure detection of the receiver cannot be incarnatedmerely by branching and monitoring part of a reception signal. Thereason therefor is that the power of the reception signal which isinputted to the receiver fluctuates every moment in accordance with aninstallation environment, the number of connected access terminals,etc., so a threshold value for deciding whether a reception power valueis normal or abnormal cannot be determined. Accordingly, the failuredetection of the receiver is generally incarnated in such a way that anyknown test signal is inputted to the receiver so as to monitor thereception state of the receiver.

The diagnostic scheme of the receiver is broadly classified into twoschemes, depending upon a method of generating the test signal. One ofthem is a scheme wherein part of the output signal of the transmittermounted in the same radio access point apparatus is branched so as touse the branched part as the test signal. This scheme is also called the“loopback test”. The other is a scheme wherein a test signal generatorfor outputting the test signal is mounted in the same radio access pointapparatus. Neither of the methods, however, cannot perform a measurementin remote and on-line fashion.

A technique for confirming the normality of the radio access pointremotely and on-line is disclosed in, for example, Patent Document 1.The technique is a method wherein a telephone within an operation centerconnected to a network including the radio access point apparatus,vocally communicates with a portable terminal within the access point,via the network, thereby to test the access point apparatus and thenetwork. Besides, Patent Document 2, for example, discloses a techniquewherein a similar test method has been expanded into a method ofconfirming the normality of a packet data call processing function, notthe vocal communications.

[Patent Document 1] JP-A-2000-332679

[Patent Document 2] JP-A-2002-271280

SUMMARY OF THE INVENTION

Each of the two prior-art examples can detect the abnormality of thereception path of the radio access point apparatus, but it has theproblem that a radio characteristic change such as a receptionperformance degradation attendant upon a slight degree of fault cannotbe decided quantitatively. A further problem is that a faulty partcannot be specified.

In order to solve the problems, the reception sensitivity of the radioaccess point apparatus needs to be measured at a high precision.Besides, in performing the receiver sensitivity measurement, theinfluence of external noise from an antenna installation must beconsidered. In an installation environment of heavy external noise, thereception sensitivity is sometimes reported to be worse than theoriginal reception sensitivity value of the access point. The reasontherefor is that the external noise inputted via the antenna issuperposed on the test signal, so the S/N (Signal To Noise Ratio) of thesignal lowers to degrade the reception sensitivity of the access point.

In view of the above points, the present invention has its object toprovide a radio access point testing apparatus and a method of testing aradio access point as measure a reception sensitivity at a highprecision. Another object of the invention is to exclude the influenceof external noise and to calibrate a measurement loop before a receiversensitivity measurement, thereby to measure a reception sensitivity at ahigh precision. Still another object of the invention is to diagnose areceiver and a signal path. Yet another object of the invention is tospecify a cause in a case, for example, where a receiver sensitivitymeasurement value as desired has not been attained.

In the invention, the reception sensitivity is measured by furnishing aradio access point apparatus with a test terminal called a “TAT (accessterminal function portion)”. The TAT is the test terminal which isendowed with the same call processing function as that of a generalaccess terminal. Owing to the endowment with the same call processingfunction as that of the general access terminal, the receptionsensitivity can be measured without influence on a general service.Besides, a radio-frequency switch is connected to an antenna input endin order to exclude a measurement error ascribable to the externalnoise. During the receiver sensitivity measurement, the switch is set soas to cut off the section between the antenna and an access pointreceiver, so as to prevent the external noise from being inputted.

Further, the normality of the path between the TAT and the access pointreceiver is confirmed using the output signal of a transmitter mountedin the access point. Thus, when the receiver sensitivity measurementvalue as desired, for example, has not been acquired, it is permitted tospecify the cause.

In order to incarnate these functions, the reception sensitivity of theaccess point is measured by the following procedure of steps in theinvention, but the measurement may well be performed by an appropriateprocedure of steps without being restricted to the indicated steps:

-   (1) Confirmation of Normality of Path between TAT and Access point    receiver-   (2) Calibrations of Path loss between TAT and Access point receiver    and Transmitter within TAT-   (3) Receiver sensitivity measurement of Access point receiver

According to a first solving means of this invention, there is provideda radio access point testing apparatus comprising:

an access terminal function portion which includes a transmitter partand a receiver part of a communication terminal in a radio communicationsystem, and which serves to test a radio access point;

either of a receiver of one loop and receivers of two loops, forreceiving forward signals that are transmitted from said access terminalfunction portion and said communication terminal;

a transmitter for transmitting reverse signals that are transmitted tosaid access terminal function portion and said communication terminal;

a path switch part for effecting switching so as to connect an input endof said receiver to an antenna or to terminate the input end, and forswitching paths of the signal from said transmitter and the signaltoward said receiver; and

an access point controller which controls said access point;

wherein said access point controller receives a test start command,terminates the input end of said receiver by said path switch part incompliance with the command, and connects a desired one of saidtransmitter and said receiver with said access terminal functionportion, so as to control either or both of:

(1) a receiver sensitivity measurement in which a packet error rate isadjusted into a predetermined range, and in which a receptionsensitivity is obtained on the basis of transmission power of saidaccess terminal function portion after the adjustment; and

(2) a measurement path diagnosis which acquires a first reception powervalue of said receiver in the case of connecting said receiver with saidtransmitter part of said access terminal function portion, and a secondreception power value of said access terminal function portion in thecase of connecting said transmitter with said receiver part of saidaccess terminal function portion, and in which failures of said receiverand the signal path are diagnosed depending upon whether or not adifference between the first reception power value and a predeterminedfirst reception power expectation, and a difference between the secondreception power value and a predetermined second reception powerexpectation lie within predetermined ranges, respectively.

According to a second solving means of this invention, there is providedin a radio access point having an access terminal function portion whichincludes a transmitter part and a receiver part of a communicationterminal in a radio communication system, and which serves to test aradio access point; either of a receiver of one loop and receivers oftwo loops, for receiving forward signals that are transmitted from theaccess terminal function portion and the communication terminal; atransmitter for transmitting reverse signals that are transmitted to theaccess terminal function portion and the communication terminal; a pathswitch part for effecting switching so as to connect an input end of thereceiver to an antenna or to terminate the input end, and for switchingpaths of the signal from the transmitter and the signal toward thereceiver; and an access point controller which controls the accesspoint;

a method of testing the radio access point, comprising:

receiving a test start command; and

terminating the input end of said receiver by said path switch part incompliance with the test start command, and connecting a desired one ofsaid transmitter and said receiver with said access terminal functionportion, so as to control either or both of:

(1) a receiver sensitivity measurement in which a packet error rate isadjusted into a predetermined range, and in which a receptionsensitivity is obtained on the basis of transmission power of saidaccess terminal function portion after the adjustment; and

(2) a measurement path diagnosis which acquires a first reception powervalue of said receiver in the case of connecting said receiver with saidtransmitter part of said access terminal function portion, and a secondreception power value of said access terminal function portion in thecase of connecting said transmitter with said receiver part of saidaccess terminal function portion, and in which failures of said receiverand the signal path are diagnosed depending upon whether or not adifference between the first reception power value and a predeterminedfirst reception power expectation, and a difference between the secondreception power value and a predetermined second reception powerexpectation lie within predetermined ranges, respectively.

Incidentally, the receiver sensitivity measurement comprises by way ofexample:

that an access point controller sets a path switch part so as to connecta receiver with a transmitter of an access terminal function portion;

that the access terminal function portion establishes a callingconnection state with a predetermined device through amodulation/demodulation process portion, and transmits packets; that theaccess point controller obtains a packet error rate;

that the access point controller commands the access terminal functionportion to alter transmission power, in accordance with the obtainedpacket error rate;

that the access terminal function portion alters the transmission powerin compliance with the command from the access point controller;

that the access terminal function portion transmits an alteredtransmission power value to the access point controller;

that the access point controller receives the transmission power value,and stores the received transmission power value in a storage unit;

that the access point controller obtains a packet error rate again;

that the access point controller judges if the obtained packet errorrate lies within a predetermined range, and that it repeats commandingthe access terminal function portion to alter transmission power andthen receiving and storing a transmission power value until the packeterror rate comes to lie within the predetermined range;

that the access point controller calculates a reception sensitivity onthe basis of the transmission power value at a time when the packeterror rate lies within the predetermined range; and

that the access point controller stores a test result which contains thecalculated reception sensitivity and/or a failure decision result basedon the reception sensitivity, in the storage unit, or transmits the testresult to a maintenance device.

According to the present invention, it is possible to provide a radioaccess point testing apparatus and a method of testing a radio accesspoint as measure a reception sensitivity at a high precision. Besides,according to the invention, the influence of external noise is excluded,and a measurement loop is calibrated before the measurement of thereception sensitivity, whereby the reception sensitivity can be measuredat a high precision. According to the invention, a receiver and a signalpath can be diagnosed. Moreover, according to the invention, in a case,for example, where a receiver sensitivity measurement value as desiredhas not been obtained, the cause of the situation can be specified.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a radio access point according to anembodiment of the present invention;

FIG. 2 is a detailed configurational diagram of the path switch part andtest function unit of sector-1 in the invention;

FIG. 3 is a diagram (1) for explaining a radio signal path in the caseof measuring the reception sensitivity of the loop-0 of the sector-1 inthe invention;

FIG. 4 is a diagram (2) for explaining a radio signal path in the caseof measuring the reception sensitivity of the loop-0 of the sector-1 inthe invention;

FIG. 5 is a diagram (3) for explaining a radio signal path in the caseof measuring the reception sensitivity of the loop-0 of the sector-1 inthe invention;

FIG. 6 is a diagram (4) for explaining a radio signal path in the caseof measuring the reception sensitivity of the loop-0 of the sector-1 inthe invention;

FIG. 7 is a diagram for explaining a sequence in the case of performinga measurement path diagnosis in the invention;

FIG. 8 is a diagram for explaining a sequence in the case of configuringa measurement system in the invention;

FIG. 9 is a diagram for explaining a sequence in the case of performingthe receiver sensitivity measurement in the invention;

FIG. 10 is a block diagram in the case of performing a reception powermeasurement in the invention;

FIG. 11 is a diagram for explaining receiver diagnoses in the invention;

FIG. 12 is an example of a receiver correcting table in the invention;and

FIG. 13 is a flow chart of normality diagnoses.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention will now be described withreference to the drawings by exemplifying a radio access point of3-sector configuration which includes a transmitter of one loop andreceivers of two loops per sector, and which incarnates diversityreception.

FIG. 1 is a configurational diagram of the radio access point. Includedin the radio access point 100 are three sectors (sector-1 110, sector-2111 and sector-3 112), a test function unit 113, a line interfaceportion 114 and an access point controller 115.

The signal processing unit (sector-1) 110 includes a radio signaltransmission/reception portion 120 and a modulation/demodulation processportion 121, and a loop-0 antenna 116 shared by transmission andreception and a loop-1 antenna 117 for reception, for example, areconnected to this signal processing unit. The radio signaltransmission/reception portion 120 includes a path switch part 132 forswitching transmission/reception paths, and the transmitter 133 of oneloop, as well as the receivers of two loops (receiver-0 134 andreceiver-1 135). Further, the radio signal transmission/receptionportion 120 includes a DUP (duplexer) 130 which separates a reverseradio signal 150 and a forward radio signal 151, and a BPF (band-passfilter) 131 which limits the pass band of the forward radio signal 151.Incidentally, the number of sectors is not limited to three, but onesector or an appropriate number of sectors may well be included.Besides, the receivers and the transmitter(s) may well be disposed inappropriate numbers of loops.

The transmitter 133 converts a reverse baseband signal 155 inputted froma modulator 136, into a reverse radio signal 152. The receiver-0 134receives the forward radio signal 151 transmitted by an access terminal101, through the DUP 130 (as a signal 153), so as to convert thereceived signal into a forward baseband signal 156. On the other hand,the receiver-1 135 receives the forward radio signal 151 transmitted bythe access terminal 101, through the BPF 131 (as a signal 154), so as toconvert the received signal into a forward baseband signal 157.Incidentally, since the configuration of each of the sector-2 111 andsector-3 112 may be identical to the configuration of the sector-1 110,it shall be omitted from description.

The modulation/demodulation process portion 121 includes the modulator136 and a demodulator 137, and it modulates and demodulates data. Theline interface portion 114 is the interface between the radio accesspoint 100 and a network 102. The access point controller 115 has thefunctions of monitoring and controlling the radio access point 100. Thetest function unit 113 includes, for example, an access terminalfunction portion 126 and a test function controller 127. Incidentally,the practicable configuration of the test function unit 113 will bedescribed later.

A maintenance terminal 103 is connected to the access point controller115 via the network 102, and it has the functions of remotely monitoringand controlling the radio access point 100. A test server 104 is aserver for testing, and the access terminal function portion 126 in thetest function unit 113 connects this test server via the network 102.

FIG. 2 is a detailed configurational diagram of the path switch part andthe test function unit. Besides, FIGS. 3-6 are diagrams (1)-(4) forexplaining radio signal paths, respectively. A receiver sensitivitymeasurement according to the embodiment of the invention will bedescribed with reference to FIGS. 2-6. Incidentally, although FIG. 2illustrates the internal configuration of the sector-1 110, each of thesector-2 111 and the sector-3 112 may be identical in configuration tothe sector-1 110 and shall therefore be omitted from description.

In this embodiment, the test function unit 113 is mounted in the radioaccess point 100, and the path switch part 132 is mounted in the radiosignal transmission/reception portion 120. The path switch part 132includes, for example, three CPLs (directional couplers) and six SWs(radio-frequency switches). Incidentally, the CPLs and the SWs may wellbe disposed in appropriate numbers without being limited to the abovenumbers.

The CPL 201 (second directional coupler) connects the transmitter is133, the DUP 130 (or a path to the antenna) and the SW 202 (or a path tothe test function unit) to one another. Besides, the CPL 204 (firstdirectional coupler) connects the SW 205 (the receiver-0 or thetransmitter), the SW 203 (a path to the antenna or a terminating partfor termination) and the SW 209 (a path to the access terminal functionportion) to one another. The CPL 207 connects the SW 208 (the receiver-1or the transmitter), the SW 206 (a path to the antenna or a terminatingpart for termination) and the SW 209 (the path to the access terminalfunction portion) to one another.

The CPL 201 extracts part of a reverse radio signal 221 so as to outputthe extracted part to the test function unit 113. The CPL 204 extractspart of the reverse radio signal extracted by the CPL 201, so as tooutput the extracted part to the test function unit 113. Besides, theCPL 204 couples a forward test signal transmitted from the test functionunit 113, to a loop-0 forward main signal path 227, so as to output theforward test signal to the receiver-0 134. The CPL 207 extracts part ofthe reverse radio signal extracted by the CPL 201, so as to output theextracted part to the test function unit 113. Besides the CPL 207couples the forward test signal transmitted from the test function unit113, to a loop-1 forward main signal path 232, so as to output theforward test signal to the receiver-1 135.

The SW 203 switches the input terminal of the receiver-0 134 so as to beconnected to the loop-0 antenna 116 through the DUP 130, or to beterminated (connected to the terminating part). Besides, the SW 206switches the input terminal of the receiver-1 135 so as to be connectedto the loop-1 antenna 117 through the BPF 131, or to be terminated(connected to the terminating part). The SW 202 switches the part 221 ofthe reverse radio signal extracted by the CPL 201, so as to be outputtedto the test function unit 113, to be outputted to the loop-0 forwardmain signal path 227, or to be outputted to the loop-1 main signal path232.

The SW 205 switches, for example, the CPL 204 so as to be connected tothe receiver-0 134, or to be connected to the transmitter 133. The SW208 switches, for example, the CPL 207 so as to be connected to thereceiver-1 135, or to be connected to the transmitter 133. By way ofexample, the SW 205 effects switching so as to output the forward testsignal transmitted from the test function unit 113, to the receiver-0134 (a signal path 303 in FIG. 4), or to output the reverse radio signalextracted by the CPL 201, to the test function unit 113 (a signal path304 in FIG. 5). The SW 208 effects switching so as to output the forwardtest signal transmitted from the test function unit 113, to thereceiver-1 135, or to output the reverse radio signal extracted by theCPL 201, to the test function unit 113. The SW 209 switches the testfunction unit 113 so as to be connected to the receiver-0 134, or to beconnected to the receiver-1 135.

In an ordinary operation mode (a non-test mode), as shown in FIG. 3 isby way of example, the SW 203 is set on the side of the loop-0 antenna116, and the SW 205 on the side of the receiver-0 134. Besides, the SW206 is set on the side of the loop-1 antenna 117, and the SW 208 on theside of the receiver-1 135. That is, a loop-0 forward radio signal and aloop-1 forward signal are respectively inputted to the demodulator 137through a signal path 301 and a signal path 302.

The test function unit 113 includes the access terminal function portion126, the test function controller 127, three switches 210, 211 and 213,and a DUP 212. Incidentally, the switches may well be disposed in anappropriate number without being restricted to the above number.Besides, the test function unit 113 may well further include a forwardlink attenuator 222 and a reverse link attenuator. The access terminalfunction portion 126 is a testing terminal which has functionsequivalent to those of the access terminal 101 which a general useruses. By way of example, the access terminal function portion 126includes a transmitter part 214 and a receiver part 215. The testfunction controller 127 controls the access terminal function portion126, and has the function of setting the three switches mounted in thetest function unit 113. The SWs 210 and 211 have the functions ofswitching the sectors to-be-tested. Besides, the SW 213 switches thepath of the reverse radio signal outputted by the transmitter 133 of theaccess point, between a signal path which extends via the forward signalpath and a signal path which does not extend via the same. The DUP 212separates the reverse test signal and the forward test signal.

FIG. 10 is a configurational diagram of the receiver. By way of example,the receiver-0 134 of the radio signal transmission/reception portion120 includes an LNA (low-noise amplifier) 601 which amplifies a receivedsignal at a low distortion, an ISO (isolator) 602, an AMP (amplifier)603, a BPF (low-pass filter) 604 which attenuates unnecessary signalcomponents other than the particular band of the receiver, and anAGC-AMP (automatic gain control amplifier) 605. Besides, the receivermay well include, for example, a memory (such as ROM) which is readablefrom the access point controller 115. The AGC-AMP 605 has the functionof varying the gain of the amplifier in accordance with input power inorder that signal power to be inputted to the demodulator 137 may beheld constant. The receiver can measure a reception power value by usingthe gain value of the AGC-AMP 605.

As an example, let's consider a case where the gain of the AGC-AMP 605is subjected to a closed loop control in order that the signal powerwhich is inputted to the demodulator 137 may become 0 (zero) dBm. Amongthe components constituting the receiver, only the AGC-AMP 605 is ofvariable gain, and the other components (for example, the LNA 601 andthe AMP 603) are of fixed gains. Accordingly, when the total of the gainvalues of all the components except the AGC-AMP 605 is denoted as a“receiver fixed gain”, the following formula holds:(Reception power)+(Receiver fixed gain)+(Gain of AGC-AMP)=0 dBmThat is,(Reception power)=−(Receiver fixed gain)−(AGC-AMP gain)Since the receiver fixed gain is a known value, the reception power canbe measured in accordance with the above formula. Incidentally, each ofthe receiver-1 135 and the receiver part 215 of the access terminalfunction portion 126 is similar in configuration to the receiver-0 134.Accordingly, the measurement of the reception power of each receiver canbe incarnated by the same scheme.(Measurement Path Diagnosis)

FIG. 7 is a diagram for explaining a sequence in the case of performinga measurement path diagnosis. A method of diagnosing the receiver-0 willbe described with reference to FIG. 7. Incidentally, since the otherreceivers can be diagnosed by the same steps of procedure, they shall beomitted from description. Besides, signals “Ack” replying to requestsshall be omitted because they are ordinarily existent.

The measurement path diagnosis is started, for example, in such a waythat a maintenance engineer inputs an instruction for the measurementpath diagnosis, to the maintenance terminal 103. Themeasurement-path-diagnosis execution instruction contains measurementconditions such as the designation of the access point for themeasurement and the designations of the sector to-be-handled and thereceiver to-be-handled. Here, description will be made assuming thediagnosis of the loop-0 of the sector-1 in the access point 100.Incidentally, apart from the input by the maintenance engineer, themeasurement path diagnosis may well be started at an appropriate timing,for example, in such a way that the measurement is started at apredetermined time in accordance with a schedule stipulated beforehand.

At a step 701, the maintenance terminal 103 notifies a diagnosis startinstruction containing the designated measurement conditions, to theaccess point controller 115 of the designated radio access point 100.Incidentally, the designations of the sector and the reception loopto-be-measured may well be omitted so as to successively conduct thetests of all the receivers of the radio access point 100.

At a step 702, the access point controller 115 receives the diagnosisstart instruction, and it commands the test function controller 127 toturn ON the power source of the access terminal function portion 126 incompliance with the received instruction. At a step 703, the testfunction controller 127 turns ON the power source of the access terminalfunction portion 126.

At a step 704, the access point controller 115 commands the path switchpart 132 and the test function unit 113 to set the switches (SW settings(2)). At a step 705, the switches of the path switch part 132 and testfunction unit 113 are set so as to pass through signal paths 302 and 303in FIG. 4. By way of example, the SW 203 is set onto the terminatingside, and the SWs 205 and 209 are respectively set onto the receiver-0sides. Besides, the SW 210 of the test function unit 113 is set onto thesector-1 side. Incidentally, how the individual SWs are set can bestipulated in accordance with SW setting commands beforehand. The signalpath 302 is a path in the ordinary operation mode. Accordingly, thereceiver-1 135 which is connected to the loop-1 antenna 117 does notincur the stop of service.

At a step 706, the access point controller 115 commands the accessterminal function portion 126 to transmit a test signal. Thetransmission command contains, for example, the settings of transmissionpower and a transmission frequency. Incidentally, the maintenanceengineer may well be permitted to designate the power and the frequencyfrom the maintenance terminal 103. At a step 707, the transmitter part214 of the access terminal function portion 126 transmits the testsignal. By way of example, the access terminal function portion 126 cantransmit packets to the test server 104 by executing ping. Incidentally,apart from the ping, an appropriate command or application fortransmitting the packets may well be executed. The transmitted signalpasses through the signal path 303 in FIG. 4, and it is inputted to thereceiver-0 134. The test signal is destined for, for example, the testserver 104, and the receiver-0 134 and the demodulator 137 can processthe test signal likewise to an ordinary reception signal. At a step 708,the access terminal function portion 126 reports the transmission power(TAT transmission power value) to the access point controller 132. Thetransmission power is reported, for example, after the test signal hasbeen transmitted for a predetermined time period or in a predeterminedquantity.

At a step 709, the access point controller 115 requests the receiver-0134 to report reception power. At a step 710, the receiver-0 134measures the reception power of the test signal. At a step 711, thereceiver-0 134 reports the measured value of the reception power (accesspoint reception power value) to the access point controller 115. Theaccess point controller 115 records the reported TAT transmission powervalue and access point reception power value in a RAM 123 at anappropriate timing (hereinbelow, the reported values shall be written as“measurement values (1)”).

At a step 712, commands for setting the switches are sent from theaccess point controller 115 to the path switch part 132 and testfunction unit 113 (SW settings (3)). At a step 713, the switches of thepath switch part 132 and test function unit 113 are set so as to passthrough the path 304 in FIG. 5. By way of example, the SW 202 is setonto the side of the forward main signal path 227, and the SW 205 ontothe side of the transmitter 133. Incidentally, the SWs 203, 209 and 210are in the same states as in FIG. 4. Besides, the SW 213 of the testfunction portion 113 is set onto the side of the forward main signalpath 227.

At a step 714, the access point controller 115 requests the transmitter133 to report the transmission power of this transmitter 133(transmission power report request). At a step 715, the transmitter 133reports the transmission power of this transmitter 133 (access pointtransmission power value) to the access point controller 115 incompliance with the transmission power report request. Either thetransmission power for a predetermined time period or the instantaneousvalue of the transmission power may be reported as the transmissionpower value.

At a step 716, the access point controller 115 requests the receiverpart 215 to report a reception power value. At a step 717, the receiverpart 215 measures reception power which is being received. At a step718, the receiver part 215 reports the measured reception power value(TAT reception power value) to the access point controller 115. Theaccess point controller 115 records the reported access pointtransmission power value and TAT reception power value in the RAM 123(hereinbelow, the reported values shall be written as “measurementvalues (2)”).

At a step 719, the access point controller 115 diagnoses the normalityof the path between the access terminal function portion 126 and thereceiver-0 134, by using the measurement values (1) and (2) recorded inthe RAM 123. The diagnosis is made in accordance with the procedure ofsteps stated below.

Initially, the normalities of the transmitter 133 of the access pointand the transmitter part 214 within the access terminal function portion126 are diagnosed using the access point transmission power value andTAT transmission power value which are recorded in the RAM 123. Theaccess point controller 115 compares the access point transmission powervalue with the transmission setting power of the transmitter 133. Whenthe difference between both the power values lies within a prescribedvalue (predetermined range), the transmitter 133 is diagnosed to benormal, and when the difference lies outside the prescribed value, thetransmitter 133 is diagnosed to be abnormal. Incidentally, thetransmission setting power of the transmitter 133 can be managed by, forexample, the access point controller 115. Alternatively, thetransmission setting power may well be acquired from another appropriatemanagement portion or from the transmitter.

The access point controller 115 compares the TAT transmission powervalue with the TAT transmission setting power of the transmitter part214. When the difference between both the power values lies within aprescribed value, the transmitter part 214 is diagnosed to be normal,and when the difference lies outside the prescribed value, thetransmitter part 214 is diagnosed to be abnormal. Incidentally, thevalue set at the step 706 can be employed as the TAT transmissionsetting power. In a case where the transmitter 133 and/or thetransmitter part 214 have/has been diagnosed to be abnormal, the accesspoint controller 115 notifies the contents of the abnormality to themaintenance terminal 103 without executing later steps, whereupon thetest is ended. The steps to be stated below will be described assumingthat the transmitters 133 and 214 are normal.

Subsequently, the normalities of the signal path 304, the receiver-0 134and the receiver part 215 in the access terminal function portion 126are diagnosed using the access point reception power value and TATreception power value which have been recorded in the RAM 123. Theexpected value or expectation of the access point reception power valueand that of the TAT reception power value can be computed as follows:(Access point reception power expectation)=(TAT transmission powervalue)−(Path loss)(TAT reception power expectation)=(Access point transmission powervalue)−(Path loss)Here, the TAT transmission power value and the access point transmissionpower value are measured values, and they have been recorded in the RAM123. Further, the path loss is a known value (design value). Therefore,the expected values or expectations of the access point reception powervalue and TAT reception power value can be computed using the abovevalues. Since, however, error factors exist in the expected values onaccount of the individual dispersions of the components, a decidingthreshold value is provided and is set at, for example, ±3 dB. When thedifferences between the expected values and the reception power valuesrecorded in the RAM 123 lie within ±3 dB, the components are decided tobe normal, and when the differences exceed ±3 dB, the components aredecided to be abnormal. Using the decided results, the normalities ofthe signal path 304, the receiver-0 134 and the receiver part 215 in theaccess terminal function portion 126 are diagnosed as stated below.

FIG. 13 is a flow chart of the normality diagnoses. Now, the normalitydiagnoses of the signal path, the receiver-0 134 and the receiver part215 in the access terminal function portion 126 will be described withreference to FIG. 13.

First, the access point controller 115 diagnoses the transmitters(S101). Since the details of the transmitter diagnoses are as statedabove, they shall be omitted from description. Subsequently, the accesspoint controller 115 obtains the expected value of the access pointreception power and that of the TAT reception power. By way of example,the access point controller 115 reads out the TAT transmission powervalue, the access point transmission power value and the path loss fromthe RAM 123, and it obtains the expected values of the access pointreception power and TAT reception power in accordance with the aboveformulae (S103).

Subsequently, the access point controller 115 judges the signal paths303 and 304, access terminal function portion 126 and receiver part 215to be normal (S109), in a case where the difference between the accesspoint reception power value reported at the step 718 and the expectedvalue of the access point reception power lies within a first range (forexample, ±3 dB) (“YES” at S105), and where the difference between theTAT reception power value reported at the step 711 and the expectedvalue of the TAT reception power lies within a second range (forexample, ±3 dB) (“YES” at S107). This case is denoted as “Case-1”.

Subsequently, the access point controller 115 diagnoses the receiverpart 215 of the access terminal function portion 126 to be abnormal(S11), in a case where the difference between the access point receptionpower value and the expected value of the access point reception powerlies within the first range (“YES” at S105), and where the differencebetween the TAT reception power value and the expected value of the TATreception power lies outside the second range (“NO” at S107). In thiscase, the access point reception power value is normal, and hence, thesignal path 303 (including a part common to the path 304) is normal.Further, the transmitter 133 of the access point is normal in view ofthe step S101. Accordingly, the receiver part 215 of the access terminalfunction portion 126 is diagnosed to be abnormal. This case is denotedas “Case-2”.

Subsequently, the access point controller 115 diagnoses the receiver 134to be abnormal (S115), in a case where the difference between the accesspoint reception power value and the expected value of the access pointreception power lies outside the first range (“NO” at S105), and wherethe difference between the TAT reception power value and the expectedvalue of the TAT reception power lies within the second range (“YES” atS113). This case is the case of deciding the access point receptionpower value to be abnormal, and the TAT reception power value to benormal. In this case, the TAT reception power value is normal, andhence, the signal path 304 (including the part common to the path 303)is normal. Further, the transmitter part 214 of the access terminalfunction portion 126 is normal in view of the step S101. Accordingly,the receiver-0 134 is diagnosed to be abnormal. This case is denoted as“Case-3”.

In a case where the difference between the access point reception powervalue and the expected value of the access point reception power liesoutside the first range (“NO” at S105), and where also the differencebetween the TAT reception power and the expected value of the TATreception power lies outside the second range (“NO” at S113), the accesspoint controller 115 can judge the paths to be abnormal, or both thereceiver 134 of the access point and the receiver part 215 of the accessterminal function portion to be abnormal. Besides, diagnoses can be madein more detail as stated below.

The access point controller 115 judges if the difference between thevalue of the access point reception power and the expected value thereofis equal to or substantially equal to the difference between the valueof the TAT reception power and the expected value thereof (S117).Incidentally, regarding the judgment on the substantial equality, by wayof example, when both the differences have a difference lying within apredetermined threshold value, they may well be judged to besubstantially equal. When the two differences are substantially equal(“YES” at S117), the access point controller 115 can make the diagnosisthat the path loss of the signal path 304 is excessive (S119). Thereason therefor is that, in the case of the excessive path loss, boththe access point reception power value and the TAT reception power valuebecome smaller than the expected values in correspondence with theexcessive loss. This case is denoted as “Case-4”.

In a case where the difference between the access point reception powervalue and the expected value of the access point reception power, andthe difference between the TAT reception power value and the expectedvalue of the TAT reception power lie outside the first and secondranges, respectively (“NO” at S105 and “NO” at S113), where thedifference between the value of the access point reception power and theexpected value thereof is not equal to the difference between the valueof the TAT reception power and the expected value thereof (“NO” atS117), and where both the access point reception power value and the TATreception power value are judged to have lower-limit values (“YES” atS121), the access point controller 115 can make the diagnosis that thesignal path 304 is disconnected (S123). The reason therefor is that, inthe case of the disconnection of the path itself, quite no signal isinputted to the receiver-0 134 and the receiver part 215 of the accessterminal function portion 126, so both the access point reception powervalue and the TAT reception power value become the lower-limit values.Incidentally, the lower-limit values can be stipulated beforehand. Thiscase is denoted as “Case-5”.

In a case where the difference between the access point reception powervalue and the expected value of the access point reception power, andthe difference between the TAT reception power value and the expectedvalue of the TAT reception power lie outside the first and secondranges, respectively (“NO” at S105 and “NO” at S113), where thedifference between the value of the access point reception power and theexpected value thereof is not equal to the difference between the valueof the TAT reception power and the expected value thereof (“NO” atS117), and where neither of the access point reception power value andthe TAT reception power value is judged to have the lower-limit value(“NO” at S121), the access point controller 115 can diagnose the signalpath 304 to be normal, and both the receiver-0 134 and the receiver part215 of the access terminal function portion 126 to be abnormal (S125).This case is denoted as “Case-6”.

Incidentally, regarding the Case-4 through Case-6, by way of example,even when the difference between the value of the access point receptionpower and the expected value thereof is equal to the difference betweenthe value of the TAT reception power and the expected value thereof atthe step S117, both the receivers might be abnormal. By way of example,accordingly, in any of the Case-4 through Case-6, the access pointcontroller 115 judges the path to be abnormal, or both the receiver-0134 and the receiver part 215 of the access terminal function portion tobe abnormal, and it may well render a judgment to the effect that theradio access point might be in any of the Case-4 through Case-6 statedabove.

FIG. 11 is a diagram for explaining the diagnosing procedure of steps.The diagnosing procedure of steps will be described by exemplifyingnumerical values, with reference to FIG. 11. By way of example, thedeciding threshold values (first and second ranges) are set at ±3 dB.Besides, assuming, for example, that the TAT transmission power value is−30 dBm and that the path loss is 40 dBm, the expected value of theaccess point reception power becomes −70 dBm in view of the aboveformula. Likewise, assuming, for example, that the access pointtransmission power value is −30 dBm and that the path loss is 40 dBm,the expected value of the TAT reception power becomes −70 dBm in view ofthe above formula. Although the two expected values will be described asthe same values here, they may well be different values.

The Case-1 corresponds to a case, for example, where the access pointreception power value is −72 dBm, where the expected value of the accesspoint reception power is −70 dBm, where the measured value of the TATreception power is −71 dBm, and where the expected value of the TATreception power is −70 dBm. The difference between the access pointreception power values becomes −2 dBm, which lies within the decidingthreshold value, and the difference between the TAT reception powervalues becomes −1 dBm, which lies within the deciding threshold value.Therefore, the receivers 134 and 215 and the path are diagnosed to benormal.

The Case-2 corresponds to a case, for example, where the access pointreception power value is −72 dBm, where the expected value of the accesspoint reception power is −70 dBm, where the measured value of the TATreception power is −80 dBm, and where the expected value of the TATreception power is −70 dBm. The difference between the access pointreception power values becomes −2 dBm, which lies within the decidingthreshold value, and the difference between the TAT reception powervalues becomes −10 dBm, which lies outside the deciding threshold value.Therefore, the receiver part 215 is diagnosed to be faulty.

The Case-3 corresponds to a case, for example, where the access pointreception power value is −85 dBm, where the expected value of the accesspoint reception power is −70 dBm, where the measured value of the TATreception power is 69 dBm, and where the expected value of the TATreception power is −70 dBm. The difference between the access pointreception power values becomes −15 dBm, which lies outside the decidingthreshold value, and the difference between the TAT reception powervalues becomes 1 dBm, which lies within the deciding threshold value.Therefore, the receiver 134 is diagnosed to be faulty.

The Case-4 corresponds to a case, for example, where the decidingthreshold values are similarly set at ±3 dBm, where the access pointreception power value is −82 dBm, where the expected value of the accesspoint reception power is −70 dBm, where the measured value of the TATreception power is −83 dBm, and where the expected value of the TATreception power is −70 dBm. The difference between the access pointreception power values becomes −12 dBm, which lies outside the decidingthreshold value, and the difference between the TAT reception powervalues becomes −13 dBm, which lies outside the deciding threshold value.The difference between the access point reception power values issubstantially equal to the difference between the TAT reception powervalues. Therefore, the path 304 is diagnosed to undergo the excessiveloss. Incidentally, the numerical value examples of the Case-5 andCase-6 shall be omitted.

In this way, the normalities of the receivers are diagnosed. Althoughthe diagnoses can be made before the receiver sensitivity measurement byway of example, they are not restricted thereto, but they may well bemade after the receiver sensitivity measurement. Incidentally, thedeciding threshold values can also be set at the start of the diagnoses.Besides, the deciding threshold values need not always be set, but themaintenance engineer can also render decisions in such a way that themeasured values (1) and (2) are transmitted to the maintenance terminal103 so as to be displayed on the display unit of this maintenanceterminal 103. Further, the computations of the differences between themeasured values and the expected values can be performed on either ofthe side of the access point controller and the side of the maintenanceterminal.

(Calibrations)

FIG. 8 is a sequence diagram for performing the calibrations of eachmeasurement loop. The calibrations of the measurement loop will bedescribed with reference to FIG. 8. Incidentally, a process to be statedbelow may be executed after the above step 719, or it may well beexecuted upon receiving a test start command for performing thecalibrations of the measurement loop, from the maintenance terminal 103.

At a step 720, the access point controller 115 commands the path switchpart 132 and the test function unit 113 to set the switches (SW settings(4)). At a step 721, in compliance with the SW setting command, theswitches of the path switch part 132 and test function unit 113 are setso as to pass through, for example, the path 303 in FIG. 4.

At a step 722, the access point controller 115 commands the accessterminal function portion 126 to transmit a test signal. The test signalmay well contain, for example, the designations of a transmission leveland a frequency. By way of example, the test signal designates thetransmission level of −70 dBm and the frequency of f2. Incidentally, thelevel and frequency of the test signal may well be designated from themaintenance terminal 103 by the maintenance engineer. At a step 723, thetransmitter part 214 of the access terminal function portion 126transmits the test signal. The transmitted signal passes through thepath 303 in FIG. 4, and is inputted to the receiver-0 134. At a step724, the access terminal function portion 126 reports transmission powerto the access point controller 115. The access point controller 115stores the reported transmission power in the RAM 123.

At a step 725, the access point controller 115 requests the receiver-0134 to report a reception power value. At a step 726, the receiver-0 134measures power being received, in compliance with the report request. Ata step 727, the receiver-0 134 reports the measured value of thereceived power to the access point controller 115. The access pointcontroller 115 stores the reported received power in the RAM 123.

At a step 728, the access point controller 115 reads the correctionvalue of each individual receiver from a ROM which is mounted in thereceiver 134. By way of example, the correction value corresponding tothe frequency f2 is read.

FIG. 12 shows a configurational example of a receiver correcting tablewhich is included in each receiver. By way of example, correction valuesare stored for respective frequencies beforehand. Each of the correctionvalues indicates, for example, the error between an actual receptionpower value in the receiver and the reported reception power value.Incidentally, although the correction values for the receivers of theloop-0 and loop-1 are listed in the single table in FIG. 12, thereceivers of the individual loops may well include the correction valuesfor the respective frequencies separately.

At a step 729, the access point controller 115 calibrates a section fromthe test function unit 113 to the input end of the receiver-0 134, onthe basis of the value reported from the receiver-0 134. A method forthe calibrations will be described below.

-   (1) The reception power value at the receiver-O end is computed in    accordance with the following computational formula:    (Actual power value at Receiver-0 end)=(Reported value of Reception    power)+Correction value-   (2) The transmitter part 214 mounted in the access terminal function    portion 126, and the reception path are calibrated on the basis of    the computed value of the above step (1).

There will be described an example in the case where the transmissionpower of the access terminal function portion 126 is −30 dBm, while thereported value of the reception power of the receivers 134 is −72 dBm,and where the correction value for the frequency f2 and the loop-0to-be-handled is −0.3 in view of the receiver correcting table shown inFIG. 12. First, the access point controller 115 computes the power atthe receivers end.(Actual power value at Receiver-0 end)=Reception power+Correctionvalue=−72+(−0.3)=−72.3 dBmThe actual reception power at the receivers end becomes −72.3 dBm inaccordance with the above formula.

Subsequently, the access point controller 115 calibrates the accessterminal function portion 126 and the reception loop. First, the accesspoint controller 115 takes the difference between the transmission powerof the access terminal function portion 126 and the actual receptionpower at the receiver end. The transmission power of the access terminalfunction portion 126 is −30 dBm, and the actual power at the receiversend is −72.3 dBm, so that the difference between the two values becomes42.3 dBm. This is the loss value of the transmitter part 214 of theaccess terminal function portion 126 and the signal path by way ofexample. Assuming that a predetermined path loss stored in, for example,a memory is 40 dBm, a deviation of 2.3 dBm is involved.

When the access terminal function portion transmits power at −27.7 dBmwhich is 2.3 dBm (calibration value) higher, inclusive of thecalibration of the path, the actual power at the receiver-0 end becomes−70 dBm. In this way, the measurement path is calibrated. Besides, theaccess point controller 115 may well store the obtained loss valueand/or a configurational value in a memory or the like. By way ofexample, the access point controller 115 may use the stored loss valueinstead of a path loss value in a receiver sensitivity measurement to bedescribed later, or it may well make a transmission power valueto-be-designated higher in correspondence with the stored calibrationvalue, at the time of a packet transmission start command.

(Receiver Sensitivity Measurement)

FIG. 9 is a sequence diagram of the receiver sensitivity measurement.Incidentally, a process to be stated below may be executed after theabove step 729, or it may well be executed upon receiving a test startcommand for performing the receiver sensitivity measurement, from themaintenance terminal 103.

At a step 829, the access point controller 115 sets the individual SWsas shown in FIG. 6 by way of example. At a step 730, the access pointcontroller 115 commands the test function controller 127 to start acalling connection. At a step 731, the test function controller 127dials up the test server 104 and establishes a calling connection state.Incidentally, connection destination information items such as the dialnumber of the test server 104 can be stored in an appropriate memorywithin the access point controller 115 or test function unit 113beforehand. At a step 732, the access terminal function portion 126gives the access point controller 115 “TAT-State alterationnotification” which contains information indicating that calling hasbeen connected. Incidentally, the access terminal function portion 126and the access point controller 115 are capable of transmitting andreceiving data therebetween through, for example, the test functioncontroller.

At a step 733, the access point controller 115 commands the accessterminal function portion 126 to start packet transmission (packettransmission start command). The packet transmission start command cancontain, for example, the calibrated power value stated before (forexample, −27.7 dBm). At a step 734, the access terminal function portion126 having received the packet transmission start command starts thepacket transmission to the server. At a step 735, the access terminalfunction portion 126 gives the access point controller 115 “TAT-Statealteration notification” which contains information indicating that thepacket transmission has been started.

At a step 736, the access point controller 115 requests the accessterminal function portion 126 to report the transmission power of thisaccess terminal function portion 126 (transmission power reportrequest). At a step 737, in compliance with the transmission outputreport request, the access terminal function portion 126 reports itstransmission power to the access point controller 115. By way ofexample, the access terminal function portion 126 reports the mean valueof the transmission power for a predetermined time period before orafter the reception of the transmission power report request.Alternatively, it may well report the instantaneous value of thetransmission power at the time of the reception of the transmissionpower report request. The access point controller 115 stores thereported transmission power value P1 in the memory.

At a step 738, the access point controller 115 acquires a PER (packeterror rate). The PER can be measured as stated below by way of example.Each of the sectors has the function of requesting the access terminalfunction portion 126 to retransmit packets which cannot be demodulateddue to errors, in demodulating a forward signal transmitted from thisaccess terminal function portion 126. It is accordingly possible tocount the number of the packets for which the re-transmission requestwas made on account of the errors (hereinbelow, called the “number ofthe error packets”), and the number of packets which were normallyreceived, among the packets of the forward signal as were received byeach sector. Each sector counts the number of the error packets and thenumber of the packets normally received, and calculates the PER inaccordance with the following formula:PER[%]=(Number of Error packets)/(Total number of Received packets)Incidentally, the total number of received packets is the total of thenumber of the error packets and the number of the packets normallyreceived.

The access point controller 115 requests, for example, the sector-1 (forexample, the demodulator 137) to report the value of the PER, and it canacquire the PER transmitted in compliance with the request.Incidentally, the access point controller 115 may well acquire thenumber of the error packets and the number of the packets normallyreceived (or the total number of the received packets), so as to obtainthe PER in accordance with the above formula. Besides, the access pointcontroller 115 stores the acquired PER in the memory.

At a step 739, the access point controller 115 commands the accessterminal function portion 126 to alter the transmission power, inaccordance with the PER (transmission power alteration command). By wayof example, in a case where the measured PER is lower than prescribedthreshold values, the access point controller 115 commands the accessterminal function portion 126 to lower the transmission power, andconversely, in a case where the PER is higher than the prescribedthreshold values, the former 115 commands the latter 126 to heighten thetransmission power. Incidentally, the transmission power of the accessterminal function portion 126 may well be altered by changing theattenuation magnitude of the forward link attenuator 222 in a statewhere this transmission power is once fixed at its value at the abovecalibration.

At a step 740, the access terminal function portion 126 alters thetransmission power in compliance with the command from the access pointcontroller 115. At a step 741, the access terminal function portion 126reports the altered transmission power to the access point controller115. At a step 742, the access point controller 115 acquires the PERagain and stores the acquired PER in the memory 123.

At a step 743, the access point controller 115 judges if the PER lieswithin the prescribed range of the threshold values. In a case where thePER lies within the prescribed range of the threshold values, the accesspoint controller 115 shifts to the processing of a step 744. On theother hand, in a case where the measured PER does not lie within theprescribed range of the threshold values, the access point controller115 returns to the processing of the step 739 and repeats the processingof the steps 739-742 and 743, thereby to adjust the transmission powerof the access terminal function portion 126 so that the PER may come tolie within the prescribed range of the threshold values.

At the step 744, the access point controller 115 records the reportedvalue of the transmission power of the access terminal function portion126 in the memory 123 as a reception sensitivity value. Alternatively,the access point controller 115 may well calculate the receptionsensitivity from the reported value of the transmission power of theaccess terminal function portion 126 and the value of the loss of thesection of the access terminal function portion 126—the receiver 134. Byway of example, the access point controller 115 reads out the reportedtransmission power value of the access terminal function portion 126 andthe path loss value by referring to the RAM 123, and it calculates thereception sensitivity in accordance with the following formula:Reception sensitivity=(Transmission power value of Access terminalfunction portion)−(Path loss value)

The transmission power of the access terminal function portion 126 asemployed here is the transmission power whose PER has been brought intothe prescribed range of the threshold values by repeating the aboveprocessing, and it is stored in the memory by way of example. Besides,the value of the path loss can be fixed to a value which can attenuatethe transmission power of the access terminal function portion 126 downto a reception sensitivity point. That is, a value which is fixedlystipulated at the design of the apparatus may well be employed as thepath loss value. Alternatively, the loss value (−42.3 dBm by way ofexample) obtained by the above calibration may well be employed. Since amanufactural dispersion is involved in the path loss value, the value ofthe loss can be measured at the manufacture of the apparatus so as tostore the measured value in an appropriate memory. Here, the “receptionsensitivity point” indicates that power value of the reception power ofthe access point 100 below which the reception becomes impossible.

Further, the access point controller 115 may well judge whether or not areceiver failure has occurred, on the basis of the reception sensitivityand in accordance with, for example, whether the reception sensitivityis greater or less than a predetermined threshold value, or whether itlies within or outside a predetermined range, so as to store a judgedresult in the memory.

At a step 745, the access point controller 115 commands the accessterminal function portion 126 to stop the packet transmission (packettransmission stop command). At a step 746, the access terminal functionportion 126 stops the packet transmission in compliance with the packettransmission stop command. At a step 747, the access terminal functionportion 126 gives the access point controller 115 “TAT-State alterationnotification” which contains information indicating that the packettransmission has been stopped.

At a step 748, the access point controller 115 commands the accessterminal function portion 126 to release the calling connection (callingconnection release command). At a step 749, the access terminal functionportion releases the calling connection in compliance with the callingconnection release command. At a step 750, the access terminal functionportion 126 gives the access point controller 115 “TAT-State alterationnotification” which contains information indicating that the callingconnection has been released.

At a step 751, the access point controller 115 commands the testfunction controller 127 to turn OFF the power source of the accessterminal function portion 126 (power source turn-OFF command). At a step752, the test function controller 127 having received the power sourceturn-OFF command turns OFF the power source of the access terminalfunction portion 126.

At a step 753, the access point controller 115 commands the path switchpart 132 and the function unit 113 to set the switches. At a step 754,the switches of the path switch part 132 and test function unit 113 areset so as to pass through the paths 301 and 302 in FIG. 3 (SW settings(1)). Thus, an ordinary operation state is resumed.

At a step 755, the access point controller 115 reports a test result tothe maintenance terminal 103. The test result can contain, for example,the reception sensitivity and/or the judged result based on thereception sensitivity. At a step 756, the maintenance terminal 103receives the test result, and it displays the received test resultand/or stores the same in a storage portion, whereupon the test isended.

Incidentally, the test can also be carried out as the three dividedstages of the measurement path diagnosis (reception path diagnosis) inFIG. 7, the measurement loop calibrations (reception sensitivitycorrection) in FIG. 8 and the receiver sensitivity measurement in FIG.9. Alternatively, the test may well be carried out in the combination ofthe reception sensitivity correction and the receiver sensitivitymeasurement, or that of the receiver sensitivity measurement and thereception path diagnosis. Further, it may well be performed in anappropriate sequence. By way of example, in a case where the receptionsensitivity has not been normally obtained in the receiver sensitivitymeasurement in FIG. 9, the reception path diagnosis in FIG. 7 may wellbe performed so as to specify a failing part.

According to the invention, the reception sensitivity of a radio accesspoint can be precisely measured without involving a serviceinterruption, remotely and on-line, and without being affected byexternal noise. Also, it is possible to provide means for specifying acause in a case where a desired sensitivity has not been attained.

The invention is applicable to, for example, industries which concern amobile communication system or access point.

1. A radio access point comprising: an access terminal function portionwhich includes a transmitter part for transmitting signals and areceiver part for receiving signals, and which serves to test the radioaccess point; either of a receiver of one loop and receivers of twoloops, for receiving forward signals that are transmitted from saidaccess terminal function portion and a communication terminal; atransmitter for transmitting reverse signals that are transmitted tosaid access terminal function portion and said communication terminal; apath switch part for switching to connect an input end of said receiverwith an antenna or not, and for switching paths of the signal from saidtransmitter and the signal toward said receiver; and a controller whichreceives a test start command, terminates the input end of said receiverby said path switch part in compliance with the command, connects adesired one of said transmitter and said receiver with said accessterminal function portion and, controls a measurement path diagnosiswhich acquires a first reception power value of said receiver in thecase of connecting said receiver with said transmitter part of saidaccess terminal function portion and, in which failures of said receiverare diagnosed depending upon whether or not a difference between thefirst reception power value and a predetermined first reception powerexpectation lie within predetermined ranges.
 2. A radio access pointcomprising: an access terminal function portion which includes atransmitter part for transmitting signals and a receiver part forreceiving signals, and which serves to test the radio access point;either of a receiver of one loop and receivers of two loops, forreceiving forward signals that are transmitted from said access terminalfunction portion and a communication terminal; a transmitter fortransmitting reverse signals that are transmitted to said accessterminal function portion and said communication terminal; a path switchpart for switching to connect an input end of said receiver with anantenna or not, and for switching paths of the signal from saidtransmitter and the signal toward said receiver; and a controller whichreceives a test start command, terminates the input end of said receiverby said path switch part in compliance with the command, connects adesired one of said transmitter and said receiver with said accessterminal function portion and, controls a measurement path diagnosiswhich acquires a second reception power value of said access terminalfunction portion in the case of connecting said transmitter with saidreceiver part of said access terminal function portion, and in whichfailures of said receiver part of said access terminal function portionare diagnosed depending upon whether or not a difference between thesecond reception power value and a predetermined second reception powerexpectation lie within predetermined ranges.
 3. A radio access pointcomprising: an access terminal function portion which includes atransmitter part for transmitting signals and a receiver part forreceiving signals, and which serves to test the radio access point;either of a receiver of one loop and receivers of two loops, forreceiving forward signals that are transmitted from said access terminalfunction portion and a communication terminal; a transmitter fortransmitting reverse signals that are transmitted to said accessterminal function portion and said communication terminal; a path switchpart for switching to connect an input end of said receiver with anantenna or not, and for switching paths of the signal from saidtransmitter and the signal toward said receiver; and a controller whichreceives a test start command, terminates the input end of said receiverby said path switch part in compliance with the command, connects adesired one of said transmitter and said receiver with said accessterminal function portion and, controls a measurement path diagnosiswhich acquires a first reception power value of said receiver in thecase of connecting said receiver with said transmitter part of saidaccess terminal function portion, and a second reception power value ofsaid access terminal function portion in the case of connecting saidtransmitter with said receiver part of said access terminal functionportion, and in which failures of said receiver and the signal path arediagnosed depending upon whether or not a difference between the firstreception power value and a predetermined first reception powerexpectation, and a difference between the second reception power valueand a predetermined second reception power expectation lie withinpredetermined ranges.
 4. A radio access point according to claim 3,wherein in the measurement path diagnosis, said controller performs:connecting said receiver and said transmitter part of said accessterminal function portion by said path switch part; causing saidtransmitter part of said access terminal function portion to transmit apredetermined test signal; acquiring the first reception power value ofsaid receiver; connecting said transmitter and said receiver part ofsaid access terminal function portion by said path switch part so thatpart of the signal from said transmitter may be received by saidreceiver part of said access terminal function portion; acquiring thesecond reception power value of said access terminal function portion;deciding whether the difference between the first reception power valueof said receiver and the predetermined first reception power expectationlies within or outside the first range; deciding whether the differencebetween the second reception power value of said access terminalfunction portion and the predetermined second reception powerexpectation lies within or outside the second range; and judging any oneof normality, a failure of said receiver, a failure of said receiverpart of said access terminal function portion, abnormality of the signalpath, and failures of both said receiver and said receiver part of saidaccess terminal function portion, in accordance with a combination ofresults of the decisions.
 5. A radio access point according to claim 4,wherein in the measurement path diagnosis, said controller furtherperforms: acquiring the first transmission power value of said accessterminal function portion in the case where said receiver is connectedwith said transmitter part of said access terminal function portion;acquiring the second transmission power value of said transmitter in thecase where said transmitter is connected with said receiver part of saidaccess terminal function portion; obtaining the first reception powerexpectation by subtracting a predetermined path loss value from thefirst transmission power value of said access terminal function portion;and obtaining the second reception power expectation by subtracting apredetermined path loss value from the second transmission power valueof said transmitter.
 6. A radio access point according to claim 4,wherein in the measurement path diagnosis, said controller furtherperforms: judging as an excessive loss of the signal path if thedifference between the first reception power value of said receiver andthe first reception power expectation is substantially equal to thedifference between the second reception power value of said accessterminal function portion and the second reception power expectation;and/or rendering a judging of disconnection of the signal path in a casewhere both the first reception power value of said receiver and thesecond reception power value of said access terminal function portionare predetermined values.
 7. A radio access point according to claim 3,wherein said path switch part includes: a first directional couplerwhich interconnects said antenna or a terminating part for termination,said access terminal function portion, and said receiver or saidtransmitter; a first switch which effects switching so as to connectsaid first directional coupler to said antenna or to said terminatingpart; a second switch which effects switching so as to connect saidfirst directional coupler to said receiver or to said transmitter; and asecond directional coupler which interconnects said transmitter, saidantenna, and the path toward said access terminal function portion,wherein said first switch is set onto the terminating side, and saidsecond switch is set onto the receiver side, thereby to connect saidreceiver with said transmitter part of said access terminal functionportion, and wherein said first switch is set onto the terminating side,and said second switch is set onto the transmitter side, thereby toconnect said transmitter with said receiver part of said access terminalfunction portion.
 8. A radio access point according to claim 3, whereinsaid controller performs: reading out a correction value which indicatesan error between an actual reception power value in said receiver andthe reported reception power value, from a storage unit where thecorrection value is stored beforehand; and correcting the acquired firstreception power value of said receiver with the correction value, and/orcorrecting a transmission power value which is to be designated for saidaccess terminal function portion, on the basis of the corrected firstreception power value and the first transmission power value of saidaccess terminal function portion, so that desired transmission power maybe transmitted from said access terminal function portion or that saidreceiver may receive desired reception power.
 9. A method of testing aradio access point which has an access terminal function portion whichincludes a transmitter part for transmitting signals and a receiver partfor receiving signals, and which serves to test a radio access point;either of a receiver of one loop and receivers of two loops, forreceiving forward signals that are transmitted from the access terminalfunction portion and a communication terminal; a transmitter fortransmitting reverse signals that are transmitted to the access terminalfunction portion and the communication terminal; a path switch part forswitching to connect an input end of the receiver with an antenna ornot, and for switching paths of the signal from the transmitter and thesignal toward the receiver; and a controller which controls the radioaccess point; the method comprising: receiving a test start command;terminating the input end of said receiver by said path switch part incompliance with the test start command, and connecting a desired one ofsaid transmitter and said receiver with said access terminal functionportion; and controlling a measurement path diagnosis which acquires afirst reception power value of said receiver in the case of connectingsaid receiver with said transmitter part of said access terminalfunction portion, and a second reception power value of said accessterminal function portion in the case of connecting said transmitterwith said receiver part of said access terminal function portion, and inwhich failures of said receiver and the signal path are diagnoseddepending upon whether or not a difference between the first receptionpower value and a predetermined first reception power expectation, and adifference between the second reception power value and a predeterminedsecond reception power expectation lie within predetermined ranges.